This thing is, seriously, the highlight of CES for me (so far) this year. 3D TVs and eBook readers are fine, but there’s nothing amazing about them. The Airnergy Charger is amazing. This little box has, inside it, some kind of circuitry that harvests WiFi energy out of the air and converts it into electricity. This has been done before, but the Airnergy is able to harvest electricity with a high enough efficiency to make it practically useful: on the CES floor, they were able to charge a BlackBerry from 30% to full in about 90 minutes, using nothing but ambient WiFi signals as a power source. The Airnergy has a battery inside it, so you can just carry it around and as long as you’re near some WiFi, it charges itself. Unlike a solar charger, it works at night and you…